Abstract
A simple slide is described in which the base is a permeable membrane so that a suspension of spermatozoa (or other cells) may be examined under controlled conditions with a microscope. An objective method of assessing the motility of spermatozoa in undiluted or diluted semen from a wide variety of species including cattle, horse, pig, rabbit, rat and sheep is described. It is well correlated with other methods of assessing motility and also with the non-return rate obtained with frozen cattle semen.